perl can access many databases, not being sure what UDB was i googled it and found https://www.ibm.com/developerworks/data/library/techarticle/dm-0512greenstein/ which implies that the standard DBI module http://search.cpan.org/~timb/DBI-1.636/DBI.pm is able to access them via the DBD::DB2 module http://search.cpan.org/dist/DBD-DB2/DB2.pod. In particular this section of DB2 may be of interest http://search.cpan.org/dist/DBD-DB2/DB2.pod#Getting_Table_information where it says Both $dbh->tables and $dbh->table_info are supported. which is nice because some of the DBD modules dont support them fully.